It would make zero sense to have SM-3 equipped Aegis vessels sailing the oceans without authorization to shoot down ballistic missiles threatening Japan. When seconds separate possible intercept and a pointless miss, the system cannot possibly rely on a call the Prime Minister's Residence and/or the Defense Minister to receive authorization.

So if authorization is standard, what has Onodera done?

According to The Asahi Shimbun, Onodera ordered the MSDF Kirishima (Photo) to sea on a training mission lasting from April 3 to April 25 -- a training mission where the captain has been given special authorization to engage in anti-missile combat activities, if he thinks circumstances merit them (Link). Had he addressed the crew before departure, Onodera's message would have been, "Sailors and officers of the Kirishima, no 'defense of Japan' stuff while you are out there -- unless. of course, it's absolutely necessary. Bon Voyage."

Bon voyage, indeed.

For those keeping score, yet another instance of extraordinary casuistry deployed by Japanese security officials in the course of conducting their daily tasks.

As you were.

Later - On Twitter Andrea Ortolani writes that the ship-to-shore communications mentioned above would like be via fax, not voice.